SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '377fa7057543c0e51f3f2772babd8834c606694d821c072ac25319e5dab08010' 
  AND token = 'ODPl01bfZEOKBwD478jq6uuVYmX0JhJMAysZu4WSFFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}